1 files changed, 202 insertions, 136 deletions

diff --git a/fs/ext4/migrate.c b/fs/ext4/migrate.c
index 5c1e27de775..ec092437d3e 100644
--- a/fs/ext4/migrate.c
+++ b/fs/ext4/migrate.c
@@ -12,21 +12,21 @@
  *
  */
 
-#include <linux/module.h>
-#include <linux/ext4_jbd2.h>
-#include <linux/ext4_fs_extents.h>
+#include <linux/slab.h>
+#include "ext4_jbd2.h"
+#include "ext4_extents.h"
 
 /*
  * The contiguous blocks details which can be
  * represented by a single extent
  */
-struct list_blocks_struct {
-	ext4_lblk_t first_block, last_block;
+struct migrate_struct {
+	ext4_lblk_t first_block, last_block, curr_block;
 	ext4_fsblk_t first_pblock, last_pblock;
 };
 
 static int finish_range(handle_t *handle, struct inode *inode,
-				struct list_blocks_struct *lb)
+				struct migrate_struct *lb)
 
 {
 	int retval = 0, needed;
@@ -39,7 +39,7 @@ static int finish_range(handle_t *handle, struct inode *inode,
 	newext.ee_block = cpu_to_le32(lb->first_block);
 	newext.ee_len   = cpu_to_le16(lb->last_block - lb->first_block + 1);
 	ext4_ext_store_pblock(&newext, lb->first_pblock);
-	path = ext4_ext_find_extent(inode, lb->first_block, NULL);
+	path = ext4_ext_find_extent(inode, lb->first_block, NULL, 0);
 
 	if (IS_ERR(path)) {
 		retval = PTR_ERR(path);
@@ -53,12 +53,14 @@ static int finish_range(handle_t *handle, struct inode *inode,
 	 * credit. But below we try to not accumalate too much
 	 * of them by restarting the journal.
 	 */
-	needed = ext4_ext_calc_credits_for_insert(inode, path);
+	needed = ext4_ext_calc_credits_for_single_extent(inode,
+		    lb->last_block - lb->first_block + 1, path);
 
 	/*
 	 * Make sure the credit we accumalated is not really high
 	 */
-	if (needed && handle->h_buffer_credits >= EXT4_RESERVE_TRANS_BLOCKS) {
+	if (needed && ext4_handle_has_enough_credits(handle,
+						EXT4_RESERVE_TRANS_BLOCKS)) {
 		retval = ext4_journal_restart(handle, needed);
 		if (retval)
 			goto err_out;
@@ -73,7 +75,7 @@ static int finish_range(handle_t *handle, struct inode *inode,
 				goto err_out;
 		}
 	}
-	retval = ext4_ext_insert_extent(handle, inode, path, &newext);
+	retval = ext4_ext_insert_extent(handle, inode, path, &newext, 0);
 err_out:
 	if (path) {
 		ext4_ext_drop_refs(path);
@@ -84,8 +86,7 @@ err_out:
 }
 
 static int update_extent_range(handle_t *handle, struct inode *inode,
-				ext4_fsblk_t pblock, ext4_lblk_t blk_num,
-				struct list_blocks_struct *lb)
+			       ext4_fsblk_t pblock, struct migrate_struct *lb)
 {
 	int retval;
 	/*
@@ -93,9 +94,10 @@ static int update_extent_range(handle_t *handle, struct inode *inode,
 	 */
 	if (lb->first_pblock &&
 		(lb->last_pblock+1 == pblock) &&
-		(lb->last_block+1 == blk_num)) {
+		(lb->last_block+1 == lb->curr_block)) {
 		lb->last_pblock = pblock;
-		lb->last_block = blk_num;
+		lb->last_block = lb->curr_block;
+		lb->curr_block++;
 		return 0;
 	}
 	/*
@@ -103,64 +105,49 @@ static int update_extent_range(handle_t *handle, struct inode *inode,
 	 */
 	retval = finish_range(handle, inode, lb);
 	lb->first_pblock = lb->last_pblock = pblock;
-	lb->first_block = lb->last_block = blk_num;
-
+	lb->first_block = lb->last_block = lb->curr_block;
+	lb->curr_block++;
 	return retval;
 }
 
 static int update_ind_extent_range(handle_t *handle, struct inode *inode,
-				   ext4_fsblk_t pblock, ext4_lblk_t *blk_nump,
-				   struct list_blocks_struct *lb)
+				   ext4_fsblk_t pblock,
+				   struct migrate_struct *lb)
 {
 	struct buffer_head *bh;
 	__le32 *i_data;
 	int i, retval = 0;
-	ext4_lblk_t blk_count = *blk_nump;
 	unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
 
-	if (!pblock) {
-		/* Only update the file block number */
-		*blk_nump += max_entries;
-		return 0;
-	}
-
 	bh = sb_bread(inode->i_sb, pblock);
 	if (!bh)
 		return -EIO;
 
 	i_data = (__le32 *)bh->b_data;
-	for (i = 0; i < max_entries; i++, blk_count++) {
+	for (i = 0; i < max_entries; i++) {
 		if (i_data[i]) {
 			retval = update_extent_range(handle, inode,
-						le32_to_cpu(i_data[i]),
-						blk_count, lb);
+						le32_to_cpu(i_data[i]), lb);
 			if (retval)
 				break;
+		} else {
+			lb->curr_block++;
 		}
 	}
-
-	/* Update the file block number */
-	*blk_nump = blk_count;
 	put_bh(bh);
 	return retval;
 
 }
 
 static int update_dind_extent_range(handle_t *handle, struct inode *inode,
-				    ext4_fsblk_t pblock, ext4_lblk_t *blk_nump,
-				    struct list_blocks_struct *lb)
+				    ext4_fsblk_t pblock,
+				    struct migrate_struct *lb)
 {
 	struct buffer_head *bh;
 	__le32 *i_data;
 	int i, retval = 0;
-	ext4_lblk_t blk_count = *blk_nump;
 	unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
 
-	if (!pblock) {
-		/* Only update the file block number */
-		*blk_nump += max_entries * max_entries;
-		return 0;
-	}
 	bh = sb_bread(inode->i_sb, pblock);
 	if (!bh)
 		return -EIO;
@@ -169,38 +156,28 @@ static int update_dind_extent_range(handle_t *handle, struct inode *inode,
 	for (i = 0; i < max_entries; i++) {
 		if (i_data[i]) {
 			retval = update_ind_extent_range(handle, inode,
-						le32_to_cpu(i_data[i]),
-						&blk_count, lb);
+						le32_to_cpu(i_data[i]), lb);
 			if (retval)
 				break;
 		} else {
 			/* Only update the file block number */
-			blk_count += max_entries;
+			lb->curr_block += max_entries;
 		}
 	}
-
-	/* Update the file block number */
-	*blk_nump = blk_count;
 	put_bh(bh);
 	return retval;
 
 }
 
 static int update_tind_extent_range(handle_t *handle, struct inode *inode,
-				     ext4_fsblk_t pblock, ext4_lblk_t *blk_nump,
-				     struct list_blocks_struct *lb)
+				    ext4_fsblk_t pblock,
+				    struct migrate_struct *lb)
 {
 	struct buffer_head *bh;
 	__le32 *i_data;
 	int i, retval = 0;
-	ext4_lblk_t blk_count = *blk_nump;
 	unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
 
-	if (!pblock) {
-		/* Only update the file block number */
-		*blk_nump += max_entries * max_entries * max_entries;
-		return 0;
-	}
 	bh = sb_bread(inode->i_sb, pblock);
 	if (!bh)
 		return -EIO;
@@ -209,16 +186,14 @@ static int update_tind_extent_range(handle_t *handle, struct inode *inode,
 	for (i = 0; i < max_entries; i++) {
 		if (i_data[i]) {
 			retval = update_dind_extent_range(handle, inode,
-						le32_to_cpu(i_data[i]),
-						&blk_count, lb);
+						le32_to_cpu(i_data[i]), lb);
 			if (retval)
 				break;
-		} else
+		} else {
 			/* Only update the file block number */
-			blk_count += max_entries * max_entries;
+			lb->curr_block += max_entries * max_entries;
+		}
 	}
-	/* Update the file block number */
-	*blk_nump = blk_count;
 	put_bh(bh);
 	return retval;
 
@@ -228,7 +203,7 @@ static int extend_credit_for_blkdel(handle_t *handle, struct inode *inode)
 {
 	int retval = 0, needed;
 
-	if (handle->h_buffer_credits > EXT4_RESERVE_TRANS_BLOCKS)
+	if (ext4_handle_has_enough_credits(handle, EXT4_RESERVE_TRANS_BLOCKS+1))
 		return 0;
 	/*
 	 * We are freeing a blocks. During this we touch
@@ -236,7 +211,7 @@ static int extend_credit_for_blkdel(handle_t *handle, struct inode *inode)
 	 * So allocate a credit of 3. We may update
 	 * quota (user and group).
 	 */
-	needed = 3 + 2*EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb);
+	needed = 3 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb);
 
 	if (ext4_journal_extend(handle, needed) != 0)
 		retval = ext4_journal_restart(handle, needed);
@@ -260,13 +235,17 @@ static int free_dind_blocks(handle_t *handle,
 	for (i = 0; i < max_entries; i++) {
 		if (tmp_idata[i]) {
 			extend_credit_for_blkdel(handle, inode);
-			ext4_free_blocks(handle, inode,
-					le32_to_cpu(tmp_idata[i]), 1, 1);
+			ext4_free_blocks(handle, inode, NULL,
+					 le32_to_cpu(tmp_idata[i]), 1,
+					 EXT4_FREE_BLOCKS_METADATA |
+					 EXT4_FREE_BLOCKS_FORGET);
 		}
 	}
 	put_bh(bh);
 	extend_credit_for_blkdel(handle, inode);
-	ext4_free_blocks(handle, inode, le32_to_cpu(i_data), 1, 1);
+	ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
+			 EXT4_FREE_BLOCKS_METADATA |
+			 EXT4_FREE_BLOCKS_FORGET);
 	return 0;
 }
 
@@ -295,7 +274,9 @@ static int free_tind_blocks(handle_t *handle,
 	}
 	put_bh(bh);
 	extend_credit_for_blkdel(handle, inode);
-	ext4_free_blocks(handle, inode, le32_to_cpu(i_data), 1, 1);
+	ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
+			 EXT4_FREE_BLOCKS_METADATA |
+			 EXT4_FREE_BLOCKS_FORGET);
 	return 0;
 }
 
@@ -306,8 +287,10 @@ static int free_ind_block(handle_t *handle, struct inode *inode, __le32 *i_data)
 	/* ei->i_data[EXT4_IND_BLOCK] */
 	if (i_data[0]) {
 		extend_credit_for_blkdel(handle, inode);
-		ext4_free_blocks(handle, inode,
-				le32_to_cpu(i_data[0]), 1, 1);
+		ext4_free_blocks(handle, inode, NULL,
+				le32_to_cpu(i_data[0]), 1,
+				 EXT4_FREE_BLOCKS_METADATA |
+				 EXT4_FREE_BLOCKS_FORGET);
 	}
 
 	/* ei->i_data[EXT4_DIND_BLOCK] */
@@ -327,7 +310,7 @@ static int free_ind_block(handle_t *handle, struct inode *inode, __le32 *i_data)
 }
 
 static int ext4_ext_swap_inode_data(handle_t *handle, struct inode *inode,
-				struct inode *tmp_inode)
+						struct inode *tmp_inode)
 {
 	int retval;
 	__le32	i_data[3];
@@ -339,7 +322,7 @@ static int ext4_ext_swap_inode_data(handle_t *handle, struct inode *inode,
 	 * i_data field of the original inode
 	 */
 	retval = ext4_journal_extend(handle, 1);
-	if (retval != 0) {
+	if (retval) {
 		retval = ext4_journal_restart(handle, 1);
 		if (retval)
 			goto err_out;
@@ -351,10 +334,21 @@ static int ext4_ext_swap_inode_data(handle_t *handle, struct inode *inode,
 
 	down_write(&EXT4_I(inode)->i_data_sem);
 	/*
+	 * if EXT4_STATE_EXT_MIGRATE is cleared a block allocation
+	 * happened after we started the migrate. We need to
+	 * fail the migrate
+	 */
+	if (!ext4_test_inode_state(inode, EXT4_STATE_EXT_MIGRATE)) {
+		retval = -EAGAIN;
+		up_write(&EXT4_I(inode)->i_data_sem);
+		goto err_out;
+	} else
+		ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
+	/*
 	 * We have the extent map build with the tmp inode.
 	 * Now copy the i_data across
 	 */
-	ei->i_flags |= EXT4_EXTENTS_FL;
+	ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
 	memcpy(ei->i_data, tmp_ei->i_data, sizeof(ei->i_data));
 
 	/*
@@ -390,7 +384,7 @@ static int free_ext_idx(handle_t *handle, struct inode *inode,
 	struct buffer_head *bh;
 	struct ext4_extent_header *eh;
 
-	block = idx_pblock(ix);
+	block = ext4_idx_pblock(ix);
 	bh = sb_bread(inode->i_sb, block);
 	if (!bh)
 		return -EIO;
@@ -406,7 +400,8 @@ static int free_ext_idx(handle_t *handle, struct inode *inode,
 	}
 	put_bh(bh);
 	extend_credit_for_blkdel(handle, inode);
-	ext4_free_blocks(handle, inode, block, 1, 1);
+	ext4_free_blocks(handle, inode, NULL, block, 1,
+			 EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
 	return retval;
 }
 
@@ -431,28 +426,27 @@ static int free_ext_block(handle_t *handle, struct inode *inode)
 			return retval;
 	}
 	return retval;
-
 }
 
-int ext4_ext_migrate(struct inode *inode, struct file *filp,
-				unsigned int cmd, unsigned long arg)
+int ext4_ext_migrate(struct inode *inode)
 {
 	handle_t *handle;
 	int retval = 0, i;
 	__le32 *i_data;
-	ext4_lblk_t blk_count = 0;
 	struct ext4_inode_info *ei;
 	struct inode *tmp_inode = NULL;
-	struct list_blocks_struct lb;
+	struct migrate_struct lb;
 	unsigned long max_entries;
+	__u32 goal;
+	uid_t owner[2];
 
-	if (!test_opt(inode->i_sb, EXTENTS))
-		/*
-		 * if mounted with noextents we don't allow the migrate
-		 */
-		return -EINVAL;
-
-	if ((EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL))
+	/*
+	 * If the filesystem does not support extents, or the inode
+	 * already is extent-based, error out.
+	 */
+	if (!EXT4_HAS_INCOMPAT_FEATURE(inode->i_sb,
+				       EXT4_FEATURE_INCOMPAT_EXTENTS) ||
+	    (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
 		return -EINVAL;
 
 	if (S_ISLNK(inode->i_mode) && inode->i_blocks == 0)
@@ -461,34 +455,35 @@ int ext4_ext_migrate(struct inode *inode, struct file *filp,
 		 */
 		return retval;
 
-	handle = ext4_journal_start(inode,
-					EXT4_DATA_TRANS_BLOCKS(inode->i_sb) +
-					EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
-					2 * EXT4_QUOTA_INIT_BLOCKS(inode->i_sb)
-					+ 1);
+	/*
+	 * Worst case we can touch the allocation bitmaps, a bgd
+	 * block, and a block to link in the orphan list.  We do need
+	 * need to worry about credits for modifying the quota inode.
+	 */
+	handle = ext4_journal_start(inode, EXT4_HT_MIGRATE,
+		4 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb));
+
 	if (IS_ERR(handle)) {
 		retval = PTR_ERR(handle);
-		goto err_out;
+		return retval;
 	}
-	tmp_inode = ext4_new_inode(handle,
-				inode->i_sb->s_root->d_inode,
-				S_IFREG);
+	goal = (((inode->i_ino - 1) / EXT4_INODES_PER_GROUP(inode->i_sb)) *
+		EXT4_INODES_PER_GROUP(inode->i_sb)) + 1;
+	owner[0] = i_uid_read(inode);
+	owner[1] = i_gid_read(inode);
+	tmp_inode = ext4_new_inode(handle, inode->i_sb->s_root->d_inode,
+				   S_IFREG, NULL, goal, owner);
 	if (IS_ERR(tmp_inode)) {
-		retval = -ENOMEM;
+		retval = PTR_ERR(tmp_inode);
 		ext4_journal_stop(handle);
-		tmp_inode = NULL;
-		goto err_out;
+		return retval;
 	}
 	i_size_write(tmp_inode, i_size_read(inode));
 	/*
-	 * We don't want the inode to be reclaimed
-	 * if we got interrupted in between. We have
-	 * this tmp inode carrying reference to the
-	 * data blocks of the original file. We set
-	 * the i_nlink to zero at the last stage after
-	 * switching the original file to extent format
+	 * Set the i_nlink to zero so it will be deleted later
+	 * when we drop inode reference.
 	 */
-	tmp_inode->i_nlink = 1;
+	clear_nlink(tmp_inode);
 
 	ext4_ext_tree_init(handle, tmp_inode);
 	ext4_orphan_add(handle, tmp_inode);
@@ -498,17 +493,33 @@ int ext4_ext_migrate(struct inode *inode, struct file *filp,
 	 * start with one credit accounted for
 	 * superblock modification.
 	 *
-	 * For the tmp_inode we already have commited the
-	 * trascation that created the inode. Later as and
+	 * For the tmp_inode we already have committed the
+	 * transaction that created the inode. Later as and
 	 * when we add extents we extent the journal
 	 */
 	/*
-	 * inode_mutex prevent write and truncate on the file. Read still goes
-	 * through. We take i_data_sem in ext4_ext_swap_inode_data before we
-	 * switch the inode format to prevent read.
+	 * Even though we take i_mutex we can still cause block
+	 * allocation via mmap write to holes. If we have allocated
+	 * new blocks we fail migrate.  New block allocation will
+	 * clear EXT4_STATE_EXT_MIGRATE flag.  The flag is updated
+	 * with i_data_sem held to prevent racing with block
+	 * allocation.
 	 */
-	mutex_lock(&(inode->i_mutex));
-	handle = ext4_journal_start(inode, 1);
+	down_read(&EXT4_I(inode)->i_data_sem);
+	ext4_set_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
+	up_read((&EXT4_I(inode)->i_data_sem));
+
+	handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
+	if (IS_ERR(handle)) {
+		/*
+		 * It is impossible to update on-disk structures without
+		 * a handle, so just rollback in-core changes and live other
+		 * work to orphan_list_cleanup()
+		 */
+		ext4_orphan_del(NULL, tmp_inode);
+		retval = PTR_ERR(handle);
+		goto out;
+	}
 
 	ei = EXT4_I(inode);
 	i_data = ei->i_data;
@@ -516,35 +527,32 @@ int ext4_ext_migrate(struct inode *inode, struct file *filp,
 
 	/* 32 bit block address 4 bytes */
 	max_entries = inode->i_sb->s_blocksize >> 2;
-	for (i = 0; i < EXT4_NDIR_BLOCKS; i++, blk_count++) {
+	for (i = 0; i < EXT4_NDIR_BLOCKS; i++) {
 		if (i_data[i]) {
 			retval = update_extent_range(handle, tmp_inode,
-						le32_to_cpu(i_data[i]),
-						blk_count, &lb);
+						le32_to_cpu(i_data[i]), &lb);
 			if (retval)
 				goto err_out;
-		}
+		} else
+			lb.curr_block++;
 	}
 	if (i_data[EXT4_IND_BLOCK]) {
 		retval = update_ind_extent_range(handle, tmp_inode,
-					le32_to_cpu(i_data[EXT4_IND_BLOCK]),
-					&blk_count, &lb);
+				le32_to_cpu(i_data[EXT4_IND_BLOCK]), &lb);
 			if (retval)
 				goto err_out;
 	} else
-		blk_count +=  max_entries;
+		lb.curr_block += max_entries;
 	if (i_data[EXT4_DIND_BLOCK]) {
 		retval = update_dind_extent_range(handle, tmp_inode,
-					le32_to_cpu(i_data[EXT4_DIND_BLOCK]),
-					&blk_count, &lb);
+				le32_to_cpu(i_data[EXT4_DIND_BLOCK]), &lb);
 			if (retval)
 				goto err_out;
 	} else
-		blk_count += max_entries * max_entries;
+		lb.curr_block += max_entries * max_entries;
 	if (i_data[EXT4_TIND_BLOCK]) {
 		retval = update_tind_extent_range(handle, tmp_inode,
-					le32_to_cpu(i_data[EXT4_TIND_BLOCK]),
-					&blk_count, &lb);
+				le32_to_cpu(i_data[EXT4_TIND_BLOCK]), &lb);
 			if (retval)
 				goto err_out;
 	}
@@ -559,9 +567,15 @@ err_out:
 		 * tmp_inode
 		 */
 		free_ext_block(handle, tmp_inode);
-	else
-		retval = ext4_ext_swap_inode_data(handle, inode,
-							tmp_inode);
+	else {
+		retval = ext4_ext_swap_inode_data(handle, inode, tmp_inode);
+		if (retval)
+			/*
+			 * if we fail to swap inode data free the extent
+			 * details of the tmp inode
+			 */
+			free_ext_block(handle, tmp_inode);
+	}
 
 	/* We mark the tmp_inode dirty via ext4_ext_tree_init. */
 	if (ext4_journal_extend(handle, 1) != 0)
@@ -584,19 +598,71 @@ err_out:
 
 	/* Reset the extent details */
 	ext4_ext_tree_init(handle, tmp_inode);
+	ext4_journal_stop(handle);
+out:
+	unlock_new_inode(tmp_inode);
+	iput(tmp_inode);
 
-	/*
-	 * Set the i_nlink to zero so that
-	 * generic_drop_inode really deletes the
-	 * inode
-	 */
-	tmp_inode->i_nlink = 0;
+	return retval;
+}
 
-	ext4_journal_stop(handle);
-	mutex_unlock(&(inode->i_mutex));
+/*
+ * Migrate a simple extent-based inode to use the i_blocks[] array
+ */
+int ext4_ind_migrate(struct inode *inode)
+{
+	struct ext4_extent_header	*eh;
+	struct ext4_super_block		*es = EXT4_SB(inode->i_sb)->s_es;
+	struct ext4_inode_info		*ei = EXT4_I(inode);
+	struct ext4_extent		*ex;
+	unsigned int			i, len;
+	ext4_fsblk_t			blk;
+	handle_t			*handle;
+	int				ret;
+
+	if (!EXT4_HAS_INCOMPAT_FEATURE(inode->i_sb,
+				       EXT4_FEATURE_INCOMPAT_EXTENTS) ||
+	    (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
+		return -EINVAL;
 
-	if (tmp_inode)
-		iput(tmp_inode);
+	if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
+				       EXT4_FEATURE_RO_COMPAT_BIGALLOC))
+		return -EOPNOTSUPP;
 
-	return retval;
+	handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
+	if (IS_ERR(handle))
+		return PTR_ERR(handle);
+
+	down_write(&EXT4_I(inode)->i_data_sem);
+	ret = ext4_ext_check_inode(inode);
+	if (ret)
+		goto errout;
+
+	eh = ext_inode_hdr(inode);
+	ex  = EXT_FIRST_EXTENT(eh);
+	if (ext4_blocks_count(es) > EXT4_MAX_BLOCK_FILE_PHYS ||
+	    eh->eh_depth != 0 || le16_to_cpu(eh->eh_entries) > 1) {
+		ret = -EOPNOTSUPP;
+		goto errout;
+	}
+	if (eh->eh_entries == 0)
+		blk = len = 0;
+	else {
+		len = le16_to_cpu(ex->ee_len);
+		blk = ext4_ext_pblock(ex);
+		if (len > EXT4_NDIR_BLOCKS) {
+			ret = -EOPNOTSUPP;
+			goto errout;
+		}
+	}
+
+	ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
+	memset(ei->i_data, 0, sizeof(ei->i_data));
+	for (i=0; i < len; i++)
+		ei->i_data[i] = cpu_to_le32(blk++);
+	ext4_mark_inode_dirty(handle, inode);
+errout:
+	ext4_journal_stop(handle);
+	up_write(&EXT4_I(inode)->i_data_sem);
+	return ret;
 }